1. Field of the Invention
The present invention relates to a flexible display device, and more particularly, to a flexible display device for smoothly guiding an operation of folding or spreading a plurality of plates on which a flexible display is attached, in a portable display device provided with a flexible display screen having bending capability.
2. Background of the Related Art
Portable terminals such as a smart phone, a tablet PC and the like which are enabled to connect to the Internet by improving cellular phones are extremely popular recently owing to development of communication techniques and advancement in semiconductor and optical techniques and has brought an innovation in science and technology since living environments of human beings are entirely changed using the portable terminals.
Particularly, although the tablet PC has an advantage of having a wide display screen, it is inconvenient to carry since it is too bulky.
Therefore, a flexible display having flexibility has been proposed to improve the problem.
As a prior technique related to a flexible display substrate which can be folded or spread, ┌Flexible display substrate┘ of Korean Patent Application No. 10-2009-0030869 has been disclosed.
A flexible display is a display which is rollable in the form of a roll or curved or bendable like a paper and has a free exterior design.
In addition, since the substrate has flexibility, the display is solid and unbreakable, and this can be understood as a thin and light display using a light substrate like plastic in some cases.
Meanwhile, the most basic form of the flexible display is folding the flexible display in half and carrying while a volume thereof is reduced by half.
Although the flexible display is folded, it cannot be bent and folded like folding a paper, it is preferable to fold the flexible display in a form having a gentle curvature.
Meanwhile, although a flexible display device according to a conventional technique has a hinge connection in most cases, in which connection parts of a plate divided into two or more pieces and a hinge unit are combined using an axis pin, there is a problem in that since a concavely bent shape remains at the middle portion of the flexible display screen even when the plate is spread, flatness of the screen is lowered.